Author Topic: Lam Cores versus Bellys  (Read 1267 times)

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Offline BrokenArrow

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Lam Cores versus Bellys
« on: August 11, 2014, 07:41:08 pm »
Can someone explain what in a tri-lam bow the core does and what the belly does?
I have seen some people use the same wood for each? Why? Is this just for show or what??

Offline Pat B

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Re: Lam Cores versus Bellys
« Reply #1 on: August 11, 2014, 08:34:10 pm »
The core is basically a filler(IMO) but needs to have shear strength. The belly should be strong in compression to withstand the compression stresses of the bow. Except for conservation of materials or to build a dramatic design I really don't see a reason to build a tri-lam bow. I've built a few and they were some of my worst performing bows. On another thought though I have added a belly lam to  backed bows that fretted or took too much set(belly cells collapsed)with good results.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline Dances with squirrels

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Re: Lam Cores versus Bellys
« Reply #2 on: August 11, 2014, 09:19:38 pm »
I've made them, love them, and will continue to do so. They are some of my best performing and aesthetically pleasing bows and outperform even glass bows of identical design and weight.

After using lams of various woods, it seems that what the core and belly lams do isn't as cut and dry as 'filler' and 'compression resistance', IMO. A flexing piece of wood is a very dynamic thing, with tension, neutral, and compression relationships changing throughout the draw and shot. I have made them with the core and belly lams with the same type of wood, and I have made them by mixing them up. I prefer them with bamboo backs and osage core and belly... although bamboo/yew/osage is quite nice too. My bow with the best shooting characteristics is such a bow.

Tri-lams allow us to make exceptional bows with wood that alone, would make something less. That said, nowadays I try to use the very best wood in them I can obtain. They can be bent and glued into shapes that backed bows cannot. Perhaps it's my imagination since I haven't done any formal testing, but they seem to require less wood and mass to make weight and/or reach or surpass the same levels of performance as many others. It's like Perry Reflex squared :^)
Straight wood may make a better bow, but crooked wood makes a better bowyer